Melanoma differentiation associated gene-7 and interleukin-24 selectively induces growth arrest and apoptosis in hepatocellular carcinoma cell lines in vitro

Objective To investigate the effect of melanoma differentiation associated gene-7/ interleukin-24 (mda-7/IL-24) on the hepatocullular carcinoma cell lines and normal liver cell line in vitro.Methods Hepatocellular carcinoma cell lines HepG2,SMMC7721,Hep3B,MHCC97L,M6 and normal liver cell line L02 were infected with Ad.mda-7.The gene expression of mda-7/IL-24 in these cell lines was confirmed by RT-PCR and ELISA assay.MTT assay and flow cytometry were used to study tumor cell proliferation and cell cycle in vitro.Hoechst staining and cytometry assay after Annexin-V and PI staining were studied to indicate the apoptosis effect.Results It was confirmed by RT-PCR that the exogenous mda- 7/IL-24 gene expressed in all of these cells.The mda-7/IL-24 protein product was confirmed by assaying the supernatant with ELISA.MTT and apoptosis test indicated mda-7/IL-24 can induce the hepatocellular carcinoma cell lines growth suppression,apoptosis in vitro but not in normal liver cell line L02,cell cycle test revealed mda-7/IL-24 can block cancer cell lines in G2/M but not in L02.Conclusions mda-7/IL-24 selectively induces growth suppression,apoptosis in hepatocellular carcinoma lines but not in normal liver cell in vitro.